1. Field of the Invention
The present invention relates to a wiring board which is to be connected to an object, and a liquid jetting head.
2. Description of the Related Art
Wiring boards which transmit and receive signals and supply electric power upon being connected to various equipments have hitherto been known. For instance, in a field of recording apparatuses including a large number of recording elements, which record an image and characters on a recording medium such as a recording paper, in order to fulfill the requirement of a high-speed printing and a high-resolution printing, in recent years, there has been a tendency toward increase in the number of recording elements and a high densification. Therefore, with the increase in the number of recording elements, contact points on a substrate of a wiring board which are to be connected to contact points on an element side connected to the recording elements have increased, leading to a high densification, and drawing around of wires to the plurality of contact points on substrate side has been complicated.
Therefore, as a structure which makes the drawing around of wires easy, in a wiring body which is to be connected to a piezoelectric actuator of an ink-jet head described in U.S. Patent Application Publication No. 2008/0316255 (corresponds to Japanese Patent Application Laid-open No. 2009-4419), two wiring boards are stacked to overlap, and a plurality of contact points on substrate side corresponding to a plurality of contact points on element side of the piezoelectric actuator, and wires to be connected to the plurality of contact points on substrate side are formed to be distributed to the two wiring boards. Moreover, in one of the wiring boards facing the piezoelectric actuator, an opening is formed at a position facing the contact points on substrate side formed on the other wiring board, and from the opening, the contact points on substrate side formed on the other wiring board are exposed toward the piezoelectric actuator. In this manner, by arranging the plurality of contact points on substrate side, to be divided on two wiring boards, the drawing around of wires to the plurality of contact points on substrate side is made easy.
However, in the wiring body described in U.S. Patent Application Publication No. 2008-0316255, a highly densified arrangement of contact points has been realized by overlapping two wiring boards, and since a distance between the contact points is substantially small, it is necessary to join two wiring boards to the piezoelectric actuator which is to be connected, upon positioning accurately. However, when the two wiring boards are separate members, to position the wiring boards with a micro distance between the contact points is difficult and takes longer time. Moreover, when a force in a direction separating away from an object is exerted to any of the two wiring boards, the force is exerted only to the contact points on substrate side formed on the wiring board to which the force has been exerted. Therefore, a joining strength is low, and exfoliation and shifting of the wiring board from the object are easily occurred.